Question

in the periodic table, the symbol p represents the element ______ the number 15 indicates that an atom of phosphorus has 15 protons in its nucleus. the textbook chemistry, by raymond chang, explains these concepts in more detail. which choice completes the text so that it conforms to the conventional english? a phosphorus b phosphorus, c phosphorus and d phosphorus, and

Explanation:

The sentence has two independent clauses. The first clause is "In the periodic table, the symbol P represents the element phosphorus" and the second is "the number 15 indicates that an atom of phosphorus has 15 protons in its nucleus". When joining two independent clauses, we can use a comma and a coordinating conjunction (like "and"). Option D ("phosphorus, and") correctly uses a comma before "and" to join the two clauses. Option A has no punctuation to join the clauses, which is a run - on. Option B only has a comma (a comma splice). Option C has "and" but no comma before it for joining independent clauses.

Answer:

D. phosphorus, and